beautypg.com

Brocade Mobility Access Point System Reference Guide (Supporting software release 5.5.0.0 and later) User Manual

Page 281

background image

Brocade Mobility Access Point System Reference Guide

271

53-1003100-01

5

17. Define the following PortFast parameters for the port channel’s MSTP configuration:

18. Set the following MSTP Configuration parameters for the port channel:

19. Refer to the Spanning Tree Port Cost table.

Define an Instance Index using the spinner control and then set the cost. The default path cost
depends on the user defined port speed. The cost helps determine the role of the port channel in
the MSTP network. The designated cost is the cost for a packet to travel from this port to the root in
the MSTP configuration. The slower the media, the higher the cost.

Enable PortFast

PortFast reduces the time required for a port to complete a MSTP state change from Blocked to
Forward. PortFast must only be enabled on ports on the wireless controller directly connected to a
server/workstation and not another hub or controller. PortFast can be left unconfigured on an
access point.
Select this option to enable drop-down menus for both the Enable PortFast BPDU Filter and Enable
PortFast BPDU Guard
options. This setting is disabled by default.

Enable PortFast BPDU
Filter

Select Enable to invoke a BPDU filter for this PortFast enabled port channel. Enabling the BPDU
filter feature ensures this port channel does not transmit or receive any BPDUs. The default setting
is None.

Enable PortFast BPDU
Guard

Select Enable to invoke a BPDU guard for this PortFast enabled port channel. Enabling the BPDU
Guard feature means this port will shutdown on receiving a BPDU. Thus, no BPDUs are processed.
The default setting is None.

Enable as Edge Port

Select this option to define this port as an edge port. Using an edge (private) port, you can isolate
devices to prevent connectivity over this port channel. This setting is disabled by default.

Link Type

Select either the Point-to-Point or Shared radio button. Selecting Point-to-Point indicates the port
should be treated as connected to a point-to-point link. Selecting Shared means this port should
be treated as having a shared connection. A port connected to a hub is on a shared link, while
one connected to a access point is a point-to-point link. Point-to-Point is the default setting.

Cisco MSTP Interoperability

Select either the Enable or Disable radio buttons. This enables interoperability with Cisco’s
version of MSTP, which is incompatible with standard MSTP. This setting is disabled by default.

Force Protocol Version

Sets the protocol version to either STP(0), Not Supported(1), RSTP(2) or MSTP(3). MSTP is the
default setting.

Guard

Determines whether the port channel enforces root bridge placement. Setting the guard to Root
ensures the port is a designated port. Typically, each guard root port is a designated port, unless
two or more ports (within the root bridge) are connected together. If the bridge receives superior
(BPDUs) on a guard root-enabled port, the guard root moves the port to a root-inconsistent STP
state. This state is equivalent to a listening state. No data is forwarded across the port. Thus, the
guard root enforces the root bridge position.

Speed

Default Path Cost

<=100000 bits/sec

200000000

<=1000000 bits/sec

20000000

<=10000000 bits/sec

2000000

<=100000000 bits/sec

200000

<=1000000000 bits/sec

20000